Display device with structure for preventing organic material overflow

ABSTRACT

A display device includes a substrate having a display area, in which an image is displayed, and a non-display area, in which no image is displayed. The non-display area is disposed on at least one side of the display area. A plurality of pixels is disposed in the display area. An encapsulation layer is disposed on the plurality of pixels. A dam unit is disposed in the non-display area. The dam unit includes a body part and a plurality of protrusions. Each of the plurality of protrusions protrudes from the body part.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2016-0094358, filed on Jul. 25, 2016, in the KoreanIntellectual Property Office, the entire contents of which are hereinincorporated by reference in their entirety.

TECHNICAL FIELD

The present disclosure relates to a display device, and morespecifically, to a display device with a structure for preventing anorganic material from overflowing past a non-display area of a substrateof the display device.

DISCUSSION OF THE RELATED ART

Display devices, such as a liquid crystal display (LCD) device, a plasmadisplay panel (PDP) device, an electrophoretic display device (e.g.e-ink), and an organic light emitting display (OLED) device, are widelyused in electronic devices.

For example, the organic light emitting display (OLED) device displaysan image by using organic light emitting devices (OLEDs) that areself-emitting so that no backlight is needed. In the organic lightemitting display (OLED) device, a non-display area of a substrate of thedisplay device may become deformed, and other defects may be generated,as a result of a liquid organic material, used as an encapsulation layerfor the OLEDs that are disposed within a display area of the substrate,overflowing into the non-display area of the substrate during amanufacturing process.

SUMMARY

A display device includes a substrate having a display area, in which animage is displayed, and a non-display area, in which no image isdisplayed. The non-display area is disposed on at least one side of thedisplay area. A plurality of pixels is disposed in the display area. Anencapsulation layer is disposed on the plurality of pixels. A dam unitis disposed in the non-display area. The dam unit includes a body partand a plurality of protrusions. Each of the plurality of protrusionsprotrudes from the body part.

A display device includes a substrate having a display area, in which animage is displayed, and a non-display area, in which no image isdisplayed. The non-display area is disposed on at least one side of thedisplay area. A plurality of pixels is disposed in the display area. Anencapsulation layer is disposed on the plurality of pixels. A dam unitis disposed in the non-display area. A reinforcing member includes amain body and a plurality of branches. Each of the plurality of branchesprotrudes from the main body.

A display device includes a substrate having a display area, in which animage is displayed, and a non-display area, in which no image isdisplayed. The non-display area is disposed on at least one side of thedisplay area. A plurality of pixels is disposed in the display area. Anencapsulation layer is disposed on the plurality of pixels. A dam unitis disposed in the non-display area. The dam unit includes a body partand a plurality of protrusions. Each of the plurality of protrusionsprotrudes from the body part. A reinforcing member is disposed in thenon-display area surrounding a side of the dam unit. The reinforcingmember includes a main body and a plurality of branches. Each of theplurality of branches protrudes from the main body.

A display device includes a substrate having a display are and anon-display area abutting the display area. A plurality of pixels isdisposed exclusively within the display area. Each of the plurality ofpixels includes an organic light emitting diode (OLED). An encapsulationlayer, including an organic material, is disposed on the plurality ofpixels. A baffle is disposed in the non-display area of the substrateand is configured to obstruct a flow of the organic material of theencapsulation layer.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the present disclosure and many of theattentant aspects thereof will be readily obtained as the same becomesbetter understood by reference to the following detailed descriptionwhen considered in connection with the accompanying drawings, wherein:

FIG. 1 is a top plan view illustrating a display device according to anexemplary embodiment of the present disclosure;

FIG. 2 is a cross-sectional view taken along line I-I′ of FIG. 1;

FIG. 3 is a top plan view conceptually illustrating a part correspondingto P1 of FIG. 1, and illustrates a disposition relation between a damunit and a reinforcing member;

FIGS. 4A to 4F are top plan views illustrating other forms of the damunit of FIG. 3;

FIGS. 5A and 5B are top plan views illustrating a disposition of theplurality of dam units of FIG. 3;

FIG. 6 is a top plan view illustrating a disposition structure of thedam unit in the display device according to an exemplary embodiment ofthe present disclosure;

FIGS. 7A and 7B are top plan views illustrating other forms of thereinforcing member of FIG. 3;

FIGS. 8A to 8C are top plan views illustrating a disposition of theplurality of reinforcing members of FIG. 3;

FIG. 9 is a circuit diagram corresponding to one pixel in the displaydevice illustrated in FIG. 1;

FIG. 10 is a top plan view corresponding to one pixel of FIG. 9;

FIG. 11 is a cross-sectional view taken along line II-II′ of FIG. 10;and

FIG. 12 is a cross-sectional view schematically illustrating a form, inwhich the display device of FIG. 11 adopts a touch screen.

DETAILED DESCRIPTION OF THE INVENTION

In describing exemplary embodiments of the present disclosureillustrated in the drawings, specific terminology is employed for thesake of clarity. However, the present disclosure is not intended to belimited to the specific terminology so selected, and it is to beunderstood that each specific element includes all technical equivalentswhich operate in a similar manner.

In the description of respective drawings, similar reference numeralsmay designate similar elements. In the accompanying drawings, sizes andshapes of structures may be exaggerated for clarity. It will beunderstood that when an element such as a layer, film, region, orsubstrate is referred to as being on another element, it can be directlyon the other element or one or more intervening elements may also bepresent.

Hereinafter, a display device according to an exemplary embodiment ofthe present disclosure will be described with reference to the drawings.

FIG. 1 is a top plan view illustrating a display device according to anexemplary embodiment of the present disclosure, and FIG. 2 is across-sectional view taken along line I-I′ of FIG. 1.

Referring to FIGS. 1 and 2, a display device according to an exemplaryembodiment of the present disclosure includes a substrate 100, aplurality of pixels PXL disposed on the substrate 100, an encapsulationlayer 200 disposed on the plurality of pixels PXL, a dam unit 300disposed on the substrate 100, and a reinforcing member 400 surroundingthe dam unit 300.

The substrate 100 includes a display area DA, and a non-display area NDAdisposed on at least one side of the display area DA.

The display area DA is an area which includes the plurality of pixelsPXL and displays an image. The image may include predetermined visualinformation, for example, a text, a video, a picture, and a 2D or 3Dimage.

The non-display area NDA is an area in which the pixels PXL are notdisposed, and an image is not displayed. A driving unit 190 driving thepixels PXL may be disposed in the non-display area NDA.

The substrate 100 may have an approximate rectangular shape, but is notlimited thereto. According to an exemplary embodiment of the presentdisclosure, the substrate 100 may include a pair of short sides whichare parallel to each other in a first direction DR1, and a pair of longsides which are parallel to each other in a second direction DR2.However, the shape of the substrate 100 is not limited thereto, and thesubstrate may have various shapes. For example, the substrate 100 may bea polygon having a closed shape including a straight side, a circle oran ellipse including a curved side, or a semicircle or a half ellipseincluding one side formed of a straight line and anther side formed of acurved line.

The substrate 100 may be formed of a flexible insulating material. Thesubstrate 100 may be formed of various materials, such as glass orpolymer metal. The substrate 100 may be, for example, an insulatingsubstrate formed of a polymer organic material. For example, theinsulating substrate may include polystyrene, polyvinyl alcohol,polymethyl methacrylate, polyethersulfone, polyacrylate, polyetherimide,polyethylene naphthalate, polyethylene terephthalate, polyphenylenesulfide, polyarylate, polyimide, polycarbonate, triacetate cellulose,and/or cellulose acetate propionate. However, the material of thesubstrate 100 is not limited thereto, and the substrate 100 may beformed of, for example, Fiber glass Reinforced Plastic (FRP).

The plurality of pixels PXL may be organic light emitting devicesincluding light emitting, but are not limited thereto, and may beimplemented in various forms, such as liquid crystal devices,electrophoretic devices, electrowetting devices. The plurality of pixelsPXL is disposed on the display area DA of the substrate 100. Each pixelPXL is a smallest unit for displaying an image. Each pixel PXL mayinclude an organic light emitting device emitting white light and/orcolor light. Each pixel PXL may emit red, green, or blue, but otheroptions are available. For example, each pixel PXL may emit a color,such as cyan, magenta, and yellow. Each pixel PXL includes a thin filmtransistor TFT connected to a wiring unit, and an organic light emittingdiode OLED connected to the thin film transistor TFT. The TFT may be anNMOS transistor.

The dam unit 300 surrounds a border of the display area DA, and the damunit is disposed within the non-display area NDA of the substrate 100.The dam unit 300 prevents the organic material from overflowing past thenon-display area NDA by controlling a flow speed of the organic materialincluded in the encapsulation layer 200.

The reinforcing member 400 surrounds a border of the dam unit 300, andis disposed within the non-display area NDA of the substrate 100. Whenan impact is applied to the substrate 100, the reinforcing member 400prevents any crack that may have been formed by the impact fromprogressing to the display area DA of the substrate 100.

Detailed descriptions of the dam unit 300 and the reinforcing member 400will be described below with reference to FIG. 3.

Hereinafter, the display device according to an exemplary embodiment ofthe present disclosure will be described. The display device may utilizea lamination sequence in the display area DA.

The substrate 100 may be formed of an insulating material, such as glassor resin. The substrate 100 may be formed of a flexible material so asto be bendable or foldable, and the substrate 100 may have asingle-layer structure or a multi-layer structure.

A buffer layer 110 is disposed on the substrate 100. The buffer layer100 may prevent impurities from being diffused from the substrate 100,and may increase the flatness of the substrate 100 (e.g. provideplanarization). The buffer layer 110 may include only a single layer,but may also include multiple layers.

The buffer layer 110 may be an inorganic insulating layer formed of aninorganic material. For example, the buffer layer 110 may be formed of asilicon nitride, a silicon oxide, a silicon oxynitride, or the like.When the buffer layer 110 includes multiple layers, the respectivelayers may be formed of the same material, or may be formed of differentmaterials. The buffer layer 110 may also be omitted.

An active pattern 120 is disposed on the buffer layer 110. The activepattern 120 is formed of a semiconductor material. The active pattern120 may include a source region SP, a drain region DP, and a channelregion CP that is disposed between the source region SP and the drainregion DP. The active pattern 120 may be a semiconductor pattern formedof polysilicon, amorphous silicon, an oxide semiconductor, and anorganic semiconductor material. Here, when the active pattern 120 isformed of the oxide semiconductor, the oxide semiconductor may includean amorphous oxide semiconductor or a crystalline oxide semiconductor.The channel region CP, which is a semiconductor pattern in whichimpurities are not doped, may be an intrinsic semiconductor. The sourceregion SP and the drain region DP may be semiconductor patterns dopedwith impurities. Impurities, such as n-type impurities, p-typeimpurities, and/or other metal dopants, may be used as the impurities.

A gate insulating layer 125 is disposed on the active pattern 120. Thegate insulating layer 125 may be an inorganic insulating layer formed ofan inorganic material. The inorganic material may include an inorganicinsulating material, such as a silicon nitride, a silicon oxide, and/ora silicon oxynitride.

A gate electrode 130 is disposed on the gate insulating layer 125. Thegate electrode 130 may cover a region corresponding to the channelregion CP of the active pattern 120. The gate electrode 130 may includegold (Au), silver (Ag), aluminum (Al), molybdenum (Mo), chromium (Cr),titanium (Ti), nickel (Ni), neodymium (Nd), and/or copper (Cu), or analloy of these metals. Further, the gate electrode 130 may include onlya single layer and the gate electrode 130 may include multiple layers,in which two or more of the above-mentioned materials are laminated.

An interlayer insulating layer 135 covering the gate electrode 130 isdisposed on the gate electrode 130. The interlayer insulating layer 135may be an inorganic insulating layer formed of an inorganic material.The inorganic material may include a silicon nitride, a silicon oxide,and/or a silicon oxynitride.

Openings passing through the gate insulating layer 125 and theinterlayer insulating layer 135 expose the source region SP and thedrain region DP of the active pattern 120.

A drain electrode 140 and a source electrode 150 are disposed on theinterlayer insulating layer 135. The drain electrode 140 and the sourceelectrode 150 are electrically connected to the drain region DP and thesource region SP by the openings formed in the gate insulating layer 125and the interlayer insulating layer 135, respectively. The drainelectrode 140 and the source electrode 150 may each include a metal. Forexample, the drain electrode 140 and the source electrode 150 may eachinclude gold (Au), silver (Ag), aluminum (Al), molybdenum (Mo), chromium(Cr), nickel (Ni), neodymium (Nd), and/or copper (Cu), and/or an alloyof the metals. Further, the drain electrode 140 and the source electrode150 may each include only a single layer. Alternatively, the drainelectrode 140 and the source electrode 150 may each include multiplelayers, in which two or more materials among the metals and the alloysare laminated.

Here, the active pattern 120, the gate electrode 130, the drainelectrode 140, and the source electrode 150 together form the thin filmtransistor TFT. A structure of the thin film transistor TFT is notlimited to the particular arrangement described herein, and variousother forms or structures of the thin film transistor may be used. Forexample, the thin film transistor TFT may be disposed in a top gatestructure, but may also be disposed in a bottom gate structure, in whichthe gate electrode 130 is disposed in a lower portion of the activepattern 120.

A passivation layer 145 is formed on the drain electrode 140 and thesource electrode 150. The passivation layer 145 may cover the thin filmtransistor and may include one or more layers. Further, the passivationlayer 145 may provide a planarized surface by easing a curve of a lowerstructure. The passivation layer 145 includes a contact hole exposing apart of the source electrode 150. The passivation layer 145 may be anorganic insulating layer formed of an organic material. The organicmaterial may include an organic insulating material, such as apolyacrylic compound, a polyimide compound, a fluorinate carboncompound, such as Teflon, and/or a benzocyclobutene compound.

The organic light emitting diode OLED is disposed on the passivationlayer 145. The organic light emitting diode OLED includes a firstelectrode 160, electrically connected to the source electrode 150, alight emitting layer 170, disposed on the first electrode 160, and asecond electrode 180 disposed on the light emitting layer 170.

Either the first electrode 160 or the second electrode 180 may be ananode electrode and the other may be a cathode electrode. For example,the first electrode 160 may be an anode electrode, and the secondelectrode 180 may be a cathode electrode.

Further, the first electrode 160 and/or the second electrode 180 may bea transmissive electrode. For example, when the organic light emittingdiode OLED is a bottom emission type organic light emitting device, thefirst electrode 160 may be a transmissive electrode, and the secondelectrode 180 may be a reflective electrode. When the organic lightemitting diode OLED is a top emission type organic light emittingdevice, the first electrode 160 may be a reflective electrode, and thesecond electrode 180 may be a transmissive electrode. When the organiclight emitting diode OLED is a dual emission type organic light emittingdevice, both the first electrode 160 and the second electrode 180 may betransmissive electrodes. According to an exemplary embodiment of thepresent disclosure, the first electrode 160 is an anode electrode, andthe organic light emitting diode OLED is a top emission organic lightemitting device.

The first electrode 160 may be disposed on the passivation layer 145.The first electrode 160 may include a reflective layer, which is capableof reflecting light, and transparent conductive layers disposed in anupper portion and a lower portion of the reflective layer. Either thereflective layer or the transparent conductive layer may be electricallyconnected to the source electrode 150 through the contact hole of thepassivation layer 145.

The reflective layer may include a material, which is capable ofreflecting light. For example, the reflective layer may include aluminum(Al), silver (Ag), chromium (Cr), molybdenum (Mo), platinum (Pt), nickel(Ni), and/or an alloy thereof.

The transparent conductive layer may include a transparent conductiveoxide. For example, the transparent conductive layer may include anindium tin oxide (ITO), an indium zinc oxide (IZO), an aluminum zincoxide (AZO), a gallium doped zinc oxide (GZO), a zinc tin oxide (ZTO), aGallium tin oxide (GTO), and/or a fluorine doped tin oxide (FTO).

A pixel defining layer 155, which divides a pixel area so as tocorrespond to each pixel PXL, is disposed on the substrate 100 on whichthe first electrode 160 and the like is disposed. The pixel defininglayer 155 may be an organic insulating layer formed of an organicmaterial. The organic material may include an organic insulatingmaterial, such as a polyacrylic compound, a polyimide compound, afluorinate carbon compound, such as Teflon, and/or a benzocyclobutenecompound. The pixel defining layer 155 exposes an upper surface of thefirst electrode 160, and protrudes from the substrate 100 along acircumference of the pixel PXL.

The light emitting layer 170 is disposed in the pixel area surrounded bythe pixel defining layer 155. The light emitting layer 170 may include alow molecular or high molecular material. The low molecular material mayinclude copper phthalocyanine (CuPc),N,N′-Di(naphthalene-1-yl)-N,N′-diphenyl-benzidine (NPB),tris-8-hydroxyquinoline aluminum (Alq₃), and the like. The materials maybe formed by a vapor depositing method. The high molecular material mayinclude EDOT, a poly-phenylenevinylene (PPV) based material, and/or apolyfluorene based material.

The light emitting layer 170 may include only a single layer, but mayalternatively include multiple layers such as various functional layers.When the light emitting layer 170 includes multiple layers, the lightemitting layer 170 may have a structure, in which a Hole Injection Layer(HIL), a Hole Transport Layer (HTL), an Emission Layer (EML), anElectron Transport Layer (ETL), and an Electron Injection Layer (EIL)are laminated in a single or complex structure. The light emitting layer170 may be formed by a screen printing method, an inkjet printingmethod, a Laser Induced Thermal Imaging (LITI) method, or the like.

The light emitting layer 170 is not necessarily limited to the structuredescribed herein, and may have various different structures.

The second electrode 180 is disposed on the light emitting layer 170.The second electrode 180 may also be connected to each pixel PXL, maycover most of the display area DA, and may be shared by the plurality ofpixels PXL.

The second electrode 180 may be used as either an anode electrode or acathode electrode according to an exemplary embodiment of the presentinvention, and when the first electrode 160 is an anode electrode, thesecond electrode 180 may be used as a cathode electrode. When the firstelectrode 160 is a cathode electrode, the second electrode 180 may beused as an anode electrode.

The second electrode 180 may be formed of a metal layer of gold (Au),silver (Ag), aluminum (Al), molybdenum (Mo), platinum (Pt), palladium(Pd), nickel (Ni), neodymium (Nd), and/or chromium (Cr). According to anexemplary embodiment of the present disclosure, the second electrode 180may include multiple layers including two or more layers having a metalthin film.

When an image is desired to be displayed on the bottom of the substrate100, the second electrode 180 may be formed of a metal reflective layerand/or a transparent conductive layer, and when an image is desired tobe displayed on top of the substrate 100, the second electrode 180 maybe formed of a transparent conductive layer.

The encapsulation layer 200 is disposed on the second electrode 180. Theencapsulation layer 200 covers the organic light emitting diode OLED toprevent moisture or oxygen from infiltrating into the organic lightemitting diode OLED. The encapsulation layer 200 may include only asingle layer, but may alternatively include multiple layers.

According to an exemplary embodiment of the present disclosure, theencapsulation layer 200 may include first to third encapsulation layerswhich are sequentially laminated on the second electrode 180. The firstto third encapsulation layers may be formed of an organic materialand/or an inorganic material. The third encapsulation layer disposed atthe outermost side may be formed of an inorganic material. According toan exemplary embodiment of the present disclosure, the firstencapsulation may be formed of an inorganic material, the secondencapsulation may be formed of an organic material or an inorganicmaterial, and the third encapsulation may be formed of an inorganicmaterial. Where the inorganic material is used, less moisture or oxygenpermeates than when the organic material is used, but elasticity orflexibility is more limited, so that the inorganic material isvulnerable to cracking. A spreading of a crack may be prevented byforming the first encapsulation layer and the third encapsulation withan inorganic material and forming the second encapsulation layer with anorganic material.

For convenience of the description, FIG. 2 illustrates that theencapsulation layer 200 completely covers the dam unit 300 in thenon-display area NDA of the substrate 100. Here, the encapsulation layerincluding the organic material in the encapsulation layer 200 may bedisposed at an inner side of the dam unit 300. The encapsulation layerincluding the inorganic material in the encapsulation layer 200 may bedisposed at an external side of the dam unit 300 while completelycovering the encapsulation layer including the organic material so as toprevent an end portion of the encapsulation layer including the organicmaterial from being exposed.

According to an exemplary embodiment of the present disclosure, anorganic insulating material, such as a polyacrylic compound, a polyimidecompound, a fluorinate carbon compound, such as Teflon, and/or abenzocyclobutene compound may be used as the organic material.Polysiloxane, a silicon nitride, a silicon oxide, and/or a siliconoxynitride may be used as the inorganic material.

The encapsulation layer 200 may be formed as either a single layer or inmultiple layers and a material of the encapsulation layer 200 need notbe limited to the materials above. Various changes may be made to thestructure and composition of the encapsulation layer 200. For example,the encapsulation layer 200 may include a plurality of organic materiallayers and a plurality of inorganic material layers which arealternately laminated.

Next, the non-display area NDA will be described. To the extent thatsome details are not described herein, it may be assumed that thesemissing details are similar to or identical to those correspondingdetails previously described.

According to an exemplary embodiment of the present disclosure, thenon-display area NDA includes the driver 190 for driving the thin filmtransistor TFT and the organic light emitting diode OLED, the dam unit300 surrounding the border of the display area DA, and the reinforcingmember 400 surrounding the dam unit 300.

The buffer layer 110 and the reinforcing member 400 are disposed on thenon-display area NDA of the substrate 100. The buffer layer 110 may havean opening OP in the non-display area. The buffer layer 110 may bespaced apart from the reinforcing member 400 with the opening OPinterposed therebetween.

The reinforcing member 400 may be formed of an inorganic insulatingmaterial including an inorganic material. Herein, the reinforcing member400 may be disposed on the same layer as that of the buffer layer 110and may be formed of the same material in the same process step as thoseof the buffer layer 110. However, the invention is not limited to this.For example, the reinforcing member 400 may be disposed on the samelayer as that of the gate insulating layer 125 of the display area DA,and the reinforcing member 400 may be formed of the same material in thesame process step as those of the gate insulating layer 125. Further,the reinforcing member 400 may be disposed on the same layer as that ofthe interlayer insulating layer 135 of the display area DA, and may beformed of the same material in the same process step as those of theinterlayer insulating layer 135.

As described above, the reinforcing member 400 may be formed in a singlelayer, but the present invention is not limited to this particulararrangement. For example, the reinforcing member 400 may be disposed indual layers, in which a first inorganic insulating layer is disposed onthe same layer as that of the buffer layer 110 and a second inorganicinsulating layer is disposed on the same layer as that of the gateinsulating layer 125. The first and second inorganic insulation layersare sequentially laminated. Further, the reinforcing member 400 may bedisposed in multiple layers, in which the first inorganic insulatinglayer is disposed on the same layer as that of the buffer layer 110, thesecond inorganic insulating layer is disposed on the same layer as thatof the gate insulating layer 125, and a third inorganic insulating layeris disposed on the same layer as that of the interlayer insulating layer135. The first, second, and third inorganic insulating layers aresequentially laminated.

The reinforcing member 400 may be formed of a metal. The reinforcingmember 400 may be formed of gold (Au), silver (Ag), aluminum (Al),molybdenum (Mo), chromium (Cr), nickel (Ni), neodymium (Nd), and/orcopper (Cu), and/or an alloy of the metals. Further, the reinforcingmember 400 may be formed as a single layer, but the present invention isnot limited to this particular arrangement. For example, the reinforcingmember 400 may be formed as multiple layers, in which two or morematerials among the metals and the alloys listed above are laminated.

When an impact is applied to the substrate 100, the reinforcing member400 prevents a crack that is formed by the impact from spreading to thedisplay area DA of the substrate 100. For example, when the reinforcingmember 400 is formed of a metal, power may be applied to the reinforcingmember 400 to determine whether the reinforcing member 400 has beendamaged by a crack.

A gate insulating layer 125 is disposed on the buffer layer 110. Thegate insulating layer 125 may have an opening OP corresponding to theopening OP of the buffer layer 110 in the non-display area.

The driver 190 is disposed on the gate insulating layer 125. The driver190 may include, for example, power supply lines and various circuitpatterns, such as an anti-static pattern.

A conductive layer 195 is disposed on the driver 190. The conductivelayer 195 may be electrically connected with the driver 190, and may beformed of the same material in the same process step as those of thefirst electrode 160 in the display area.

The dam unit 300 is disposed on the conductive layer 195. The dam unit300 may be formed of an organic insulating material including an organicmaterial. For example, the dam unit 300 may include only a single layer,which is disposed on the same layer as that of the pixel defining layer155 of the display area DA and is formed of the same material in thesame process step as those of the pixel defining layer 155. However, theparticular arrangement of the dam unit 300 is not limited to thestructure described herein. For example, the dam unit 300 may includeonly a single layer, which is disposed on the same layer as that of thepassivation layer 145 of the display area DA, and may be formed of thesame material in the same process step as those of the passivation layer145. Further, the dam unit 300 may include dual layers, in which a firstorganic insulating layer is disposed on the same layer as that of thepassivation layer 145 and a second organic insulating layer is disposedon the same layer as that of the pixel defining layer 155. The first andsecond organic insulating layers are sequentially laminated.

For the convenience of the description, FIG. 2 illustrates that the damunit 300 is disposed on the same layer as that of the pixel defininglayer 155.

The dam unit 300 prevents the organic material included in theencapsulation layer 200 from flowing past the non-display area duringthe manufacturing process. For example, the dam unit 300 may prevent theorganic material from overflowing beyond the non-display area NDA bycontrolling a flow speed of the organic material included in theencapsulation layer 200.

FIG. 3 is a top plan view conceptually illustrating a part correspondingto P1 of FIG. 1, and illustrates a disposition relation between the damunit and the reinforcing member.

Referring to FIGS. 1 and 3, A dam unit 300 and A reinforcing member 400are disposed in the non-display area NDA of the substrate 100.

The dam unit 300 is disposed in the non-display area NDA whilesurrounding the border of the display area DA of the substrate 100. Thedam unit 300 includes a body part 310 extended in a predetermineddirection (for example, a vertical direction) and a plurality ofprotrusions 320 protruding from the body part 310. The plurality ofprotrusions 320 may protrude in a different direction from the directionof extension of the body part 310. For example, when the body part 310extends in the predetermined direction, the plurality of protrusions 320may protrude in another direction (for example, a horizontal direction)crossing the predetermined direction.

The body part 310 of the dam unit 300 may be disposed between thedisplay area DA (see FIG. 1) and the plurality of protrusions 320. Eachof the plurality of protrusions 320 may protrude from one surface of thebody part 310, may face the reinforcing member 400, and may have arectangular shape when viewed on a plane. The body part 310 and theplurality of protrusions 320 may be integrally formed, and may be formedof an organic insulating material including an organic material. Each ofthe plurality of protrusions 320 is spaced apart from an adjacentprotrusion by a predetermined interval, and cavities 330 may be disposedbetween the protrusions 320. The dam unit 300 may have a comb shape whenviewed on a plane.

When an organic material included in the encapsulation layer 200 (seeFIG. 2) moves to the non-display area NDA of the substrate 100 during amanufacturing process, the organic material may run up against the bodypart 310 of the dam unit 300, so that a flow speed of the organicmaterial may be decreased. Further, when the organic material climbsover the body part 310 and continuously flows to the non-display area,the organic material may come to rest in the cavities 330 between theplurality of protrusions 320 and a flow speed of the organic materialmay be decreased. Accordingly, it is possible to prevent the organicmaterial from completely overflowing past the non-display area NDA ofthe substrate 100. Here, the dam unit 300 may serve as an obstacle, suchas a baffle, which decreases a flow speed of the organic material.

Further, when external light is incident to the display device,according to an exemplary embodiment of the present disclosure, lightinterference is generated in the plurality of protrusions 320 by thecomb shape of the plurality of protrusions 320. Through the lightinterference, the organic material, which may overflow past the dam unit300, is viewed, so that it is possible to confirm a boundary of theorganic material, e.g. it is possible to see where the organic materialcame to rest. As a result, it is possible to prevent defects in displaypanels that may be caused by an overflow of the organic material byconfirming the boundary of the organic material flowing to thenon-display area NDA.

The reinforcing member 400 is disposed in the non-display area NDA so asto surround a border of the dam unit 300. The reinforcing member 400includes a main body 410 extended in the predetermined direction and aplurality of branches 420 protruding from the main body 410. Theplurality of branches 420 may protrude in a different direction from thedirection of extension of the main body 410. For example, when the mainbody 410 extends in the predetermined direction, the plurality ofbranches 420 may extend in a diagonal direction inclined with respect tothe predetermined direction. Here, when the main body 410 extends in thesame direction as that of the body part 310 of the dam unit 300 whenviewed on a plane.

The main body 410 of the reinforcing member 400 may be disposed at theoutermost side within the non-display area NDA of the substrate 100. Theplurality of branches 420 of the reinforcing member 400 may protrudefrom one surface of the main body 410 so as to face the dam unit 300.

The main body 410 and the plurality of branches 420 may be integrallyformed, and may be an inorganic insulating material including aninorganic material. Each of the plurality of branches 420 is spacedapart from an adjacent branch by a predetermined interval Cavities 430may be disposed between the branches 420. The plurality of branches 420may have a comb shape when viewed on a plane.

The plurality of branches 420 of the reinforcing member 400 and theplurality of protrusions 320 of the dam unit 300 may be disposed so asto face one another in the non-display area NDA of the substrate 100,when viewed on a plane.

When viewed on a plane, a width d1 in a horizontal direction of the mainbody 410 within the non-display area NDA of the substrate 100 may bedifferent from a width d2 in a horizontal direction of each of theplurality of branches 420. Hereinafter, for convenience of description,the width d1 in the horizontal direction of the main body 410 isreferred to as a first width d1, and the width d2 in the horizontaldirection of each of the plurality of branches 420 is referred to as asecond width d2.

The second width d2 may be larger than the first width d1. For example,a ratio of the second width d2 and the first width d1 may be 3:1 to 2:1.

When an impact is applied to the substrate 100, a crack may be formed bythe impact and the crack may progress in a direction of the display areaDA of the substrate 100 via the reinforcing member 400.

When the second width d2 is equal to or smaller than the first width d1and an impact is applied to the substrate 100, a progress path of acrack that is generated by the impact is shortened and the crack istransferred to the display area DA of the substrate 100, thereby causinga defect of the substrate 100.

Further, when an impact is applied to the substrate 100 and thereinforcing member 400 includes only the main body 410, a progress pathof a crack caused by the impact is shortened and the crack istransferred to the display area DA of the substrate 100, thereby causinga defect of the substrate 100.

According to an exemplary embodiment of the present disclosure, thereinforcing member 400 is designed so that the width d2 in thehorizontal direction of the plurality of branches 420 is larger than thewidth d1 in the horizontal direction of the main body 410. When animpact is applied to the substrate 100, a crack caused by the impactprogresses to each of the plurality of branches 420 via the main body410 of the reinforcing member 400, and the width d2 in the horizontaldirection of the plurality of branches 420 is increased, so that theprogress path of the crack is increased. When the progress path of thecrack is increased, the progression of the crack may be dispersed and/orblocked when the crack progresses from the reinforcing member 400 to thedisplay area DA. Accordingly, even when an impact is applied to thesubstrate 100, it is possible to keep the crack from progressing intothe display area DA of the substrate 100. As a result, the reinforcingmember 400 may block the crack from being transferred to the displayarea DA of the substrate 100, thereby increasing the mechanical strengthof the display device.

Further, when an external light is directed to the display device, lightinterference may be generated in the plurality of branches 420 by thecomb shape of the plurality of branches 420. Through the lightinterference, the organic material of the encapsulation layer 200 (seeFIG. 2), which may climb over the dam unit 300 and overflow to theoutside of the dam unit 300, may be observed/viewed and a boundary ofthe organic material may be identified.

It is to be noted that while the figures show a one-to-onecorrespondence between the dam units 300 and the reinforcing members 400on each side of the substrate 100, the present invention is not limitedto this arrangement and each side of the substrate 100 may have adifferent number of dam units 300 and/or reinforcing members 400.

There may be one or more dam units 300 surrounding the display area DAalong the border of the display area DA of the substrate 100, and thenumber and configuration of these dam units 300 may be different byregion. Further, there may be one or more reinforcing members 400surrounding the dam unit 300 along the border of the dam unit 300 withinthe non-display area of the substrate 100, and the number andconfiguration of these reinforcing members 400 may also be different byregion.

According to an exemplary embodiment of the present disclosure, the damunit 300 may have various shapes, and FIGS. 4A to 4F are top plan viewsillustrating various shapes of the dam unit according to exemplaryembodiments of the present disclosure.

FIGS. 4A to 4F are top plan views illustrating other forms of the damunit of FIG. 3.

First, referring to FIGS. 3 and 4A, the dam unit 300 includes a bodypart 310 and a plurality of protrusions 320 protruding from the bodypart 310.

The body part 310 may extend in a predetermined direction (for example,a vertical direction). The plurality of protrusions 320 may protrude ina different direction from the direction of extension of the body part310. For example, when the body part 310 extends in the predetermineddirection, the plurality of protrusions 320 may protrude in anotherdirection (for example, a horizontal direction) crossing thepredetermined direction.

The body part 310 and the plurality of protrusions 320 may be integrallyformed, and the integral formation may be an organic insulating materialincluding an organic material.

When viewed on a plane, each of the plurality of protrusions 320 mayprotrude from one surface of the body part 310 and may have a moirépattern shape including a side formed of a straight line and a curveline. Each of the plurality of protrusions 320 is spaced apart from anadjacent protrusion by a predetermined interval, and cavities 330 may bedisposed between the protrusions. The cavity 330 may have a moirépattern shape corresponding to the shape of the plurality of protrusions320.

When an organic material included in the encapsulation layer 200 (seeFIG. 2) moves to the non-display area of the substrate 100 during amanufacturing process, the organic material may run up against the bodypart 310, so that a flow speed of the organic material may be decreased.When the organic material climbs over the body part 310, the organicmaterial may come to rest in the cavities 330 and a flow speed of theorganic material may be decreased. For example, in FIG. 4A, theplurality of protrusions 320 and the cavities 330 have the moiré patternshapes, so that contact areas between the organic material and theplurality of protrusions 320 may be increased and a flow speed of theorganic material may be decreased.

Referring to FIGS. 3 and 4B, the dam unit 300 includes a body part 310extended in a predetermined direction (for example, a verticaldirection) and a plurality of protrusions 320 protruding from the bodypart 310. The plurality of protrusions 320 may protrude in a differentdirection from the direction of extension of the body part 310.

When viewed on a plane, each of the plurality of protrusions 320 mayprotrude from one surface of the body part 310 and may have a polygonalshape including a side formed of a straight line. For example, each ofthe plurality of protrusions 320 may have a polygonal shape, of which awidth decreases farther from the body part 310. Each of the plurality ofprotrusions 320 is spaced apart from an adjacent protrusion by apredetermined interval, and cavities 330 may be disposed between theprotrusions. The cavity 330 may have a polygonal shape corresponding tothe shape of the plurality of protrusions 320. For example, a width ofthe cavity 330 may increase farther from the body part 310.

When an organic material included in the encapsulation layer 200 (seeFIG. 2) moves to the non-display area of the substrate 100 during amanufacturing process, the organic material may run up against the bodypart 310, so that a flow speed of the organic material may be decreased.When the organic material climbs over the body part 310, the organicmaterial may come to rest in the cavities 330 and a flow speed of theorganic material may be decreased. For example, in FIG. 4B, the cavity330 has the polygonal shape, of which the width increases farther fromthe body part 310, so that a flow speed of the organic material may bedecreased.

Referring to FIGS. 3 and 4C, the dam unit 300 includes a body part 310extended in a predetermined direction (for example, a verticaldirection) and a plurality of protrusions 320 protruding from the bodypart 310.

When viewed on a plane, each of the plurality of protrusions 320 mayhave a triangular shape, of which the width is increased as being farfrom the body part 310. Each of the plurality of protrusions 320 isspaced apart from an adjacent protrusion by a predetermined interval,and cavities 330 may be disposed between the protrusions. The cavity 330may have a triangular shape corresponding to the shape of the pluralityof protrusions 320. For example, a width of the cavity 330 may decreasefarther from the body part 310.

Referring to FIGS. 3 and 4D, the dam unit 300 includes a body part 310extended in a predetermined direction (for example, a verticaldirection) and a plurality of protrusions 320 protruding from the bodypart 310.

When viewed on a plane, each of the plurality of protrusions 320 mayhave a polygonal shape, which includes a straight side, and of which awidth increases and then decreases farther from the body part 310,however, the shape of each of the plurality of protrusions 320 is notlimited to any of the particular shapes described herein. For example,each of the plurality of protrusions 320 may have an elliptical shape,which includes a side formed of a curved line, and of which a widthincreases and then decreases farther from the body part 310.

For example, the plurality of protrusions 320 may have a shape which isbilaterally symmetric based on a virtual line BL disposed at a center ofthe plurality of protrusions 320. Here, a width of each of the pluralityof protrusions 320 may be approximately 10 μm to 65 μm.

The cavity 330 disposed between the plurality of protrusions 320 mayhave a polygonal shape, of which a width decreases farther from the bodypart 310 and increases when passing through the virtual line BL.

In a case where the cavity 330 has the same width and a rectangularshape when viewed on a plane, when the organic material of theencapsulation layer 200 (see FIG. 2) flows to the non-display area, aflow speed of the organic material may be increased by capillary forcein the cavity 330. Accordingly, the organic material may overflow thedam unit 300.

Accordingly, the dam unit 300, according to an exemplary embodiment ofthe present disclosure, may be designed so that each of the plurality ofprotrusions 320 has a polygonal shape that increases the contact areasbetween the organic material and the plurality of protrusions 320,thereby reducing capillary force and decreasing a flow speed of theorganic material. Further, in the dam unit 300, the cavity 330, in whichthe organic material comes to rest, has a different width, therebydecreasing a flow speed of the organic material. Accordingly, it ispossible to prevent the organic material of the encapsulation layer 200from overflowing the dam unit 300.

Referring to FIGS. 3 and 4E, the dam unit 300 includes a body part 310extended in a predetermined direction (for example, a verticaldirection) and a plurality of protrusions 320 protruding from the bodypart 310.

When viewed on a plane, each of the plurality of protrusions 320 mayhave a polygonal shape, of which a width increases farther from the bodypart 310 and then decreases again. Further, the cavity 330 disposedbetween the plurality of protrusions 320 may have a polygonal shape, ofwhich a width decreases farther from the body part 310 and thenincreases again.

Referring to FIGS. 3 and 4F, the dam unit 300 includes a body part 310extended in a predetermined direction (for example, a verticaldirection) and a plurality of protrusions 320 protruding from the bodypart 310.

The plurality of protrusions 320 may protrude in a different directionfrom the direction of extension of the body part 310. For example, whenthe body part 310 extends in the predetermined direction, each of theplurality of protrusions 320 may protrude in another direction (forexample, a horizontal direction) crossing the predetermined direction.Here, the plurality of protrusions 320 protrude from the other surfaceof the body part 310 so as to face the display area DA (see FIG. 2) ofthe substrate 100, and each of the plurality of protrusions 320 may havea rectangular shape including straight sides, when viewed on a plane.

Each of the plurality of protrusions 320 is spaced apart from anadjacent protrusion by a predetermined interval, and cavities 330 may bedisposed between the protrusions.

FIGS. 5A and 5B are top plan views illustrating a disposition of theplurality of dam units of FIG. 3.

First, referring to FIGS. 3 and 5A, first to third dam units 300 a, 300b, and 300 c may be disposed in the non-display area of the substrate100.

The first dam unit 300 a is disposed between the border of the displayarea DA (see FIG. 2) and the second dam unit 300 b, the second dam unit300 b is disposed between the first dam unit 300 a and the third damunit 300 c, and the third dam unit 300 c is disposed between thereinforcing member 400 and the second dam unit 300 b. The first to thirddam units 300 a, 300 b, and 300 c may be formed of an organic insulatingmaterial including an organic material.

The first dam unit 300 a and the second dam unit 300 b may extend in apredetermined direction (for example, a vertical direction), and mayhave a rectangular shape including straight sides.

The third dam unit 300 c includes a body part 310 and a plurality ofprotrusions 320 protruding from the body part 310. The body part 310 mayextend in the predetermined direction. The plurality of protrusions 320may protrude in a different direction from the direction of extension ofthe body part 310. For example, when the body part 310 extends in thepredetermined direction, the plurality of protrusions 320 may protrudein another direction (for example, a horizontal direction) crossing thepredetermined direction.

When viewed on a plane, each of the plurality of protrusions 320 mayprotrude from one surface of the body part 310 and may have arectangular shape including a side formed of a straight line. Each ofthe plurality of protrusions 320 is spaced apart from an adjacentprotrusion by a predetermined interval, and cavities 330 may be disposedbetween the protrusions.

The third dam unit 300 c, which is disposed at the outermost side amongthe first to third dam units 300 a, 300 b, and 300 c, may have a combshape when viewed on a plane. The third dam unit 300 c may serve as anobstacle/baffle decreasing a flow speed of the organic material when theorganic material included in the encapsulation layer 200 (see FIG. 2)moves to the non-display area of the substrate 100.

FIG. 3 illustrates that the third dam unit 300 c, which is disposed atthe outermost side among the first to third dam units 300 a, 300 b, and300 c, includes the body part 310 and the plurality of protrusions 320,however, the present invention is not limited to this particulararrangement of the dam units. For example, as illustrated in FIG. 5B,each of the first to third dam units 300 a, 300 b, and 300 c may includethe body part 310 and the plurality of protrusions 320 protruding fromthe body part 310.

FIG. 6 is a top plan view illustrating a disposition structure of a damunit in a display device according to an exemplary embodiment of thepresent disclosure. In FIG. 6, a reinforcing member is disposed on asubstrate, but for convenience of the description, the illustration ofthe reinforcing member is omitted.

Referring to FIG. 6, a display device according to an exemplaryembodiment of the present disclosure includes a substrate 100 and a damunit 300 disposed on the substrate 100.

The substrate 100 includes a display area DA and a non-display area NDAdisposed at least one side of the display area DA.

The substrate 100 may have an approximately square shape, for example, arectangular shape. According to an exemplary embodiment of the presentdisclosure, the substrate 100 may include a pair of short sides S1 andS3 that are parallel to each other in a first direction DR1, and a pairof long sides S2 and S4 that are parallel to each other in a seconddirection DR1.

The non-display area NDA may be divided into first to third areas FA,SA, and TA along the pair of long sides S2 and S4.

The dam unit 300 includes a body part 310 surrounding a border of thedisplay area DA within the non-display area NDA, and extended in thefirst direction DR1, and a plurality of protrusions 320 protruding fromthe body part 310.

The plurality of protrusions 320 may be disposed at various positionsand/or various densities per unit area according to the degree ofoverflow of the organic material included in the encapsulation layer 200(see FIG. 2). For example, in the second area SA of the non-display areaNDA, in which the large amount of organic material tends to overflow,and in the first and second areas FA and TA of the non-display area NDA,in which the organic material tends to overflows less, a relativelylarge number of protrusions 320 may be disposed in the second area SA,and a smaller number of protrusions 320, than that of the protrusions320 in the second area SA, may be disposed in the first and third areasFA and TA.

However, the present disclosure is not limited to this particulararrangement of protrusions 320.

As described above, the number of protrusions 320 to be disposed may bedifferent for each area.

FIGS. 7A and 7B are top plan views illustrating other forms of thereinforcing member of FIG. 3.

Referring to FIGS. 3 and 7A, the reinforcing member 400 includes a firstmain body 410 a and a second main body 410 b, which are each extended ina predetermined direction (for example, a vertical direction) and arearranged to face each other. Further, the reinforcing member 400includes a plurality of branches 420 disposed between the first mainbody 410 a and the second main body 410 b. The first main body 410 a,the second main body 410 b, and the plurality of branches 420 may beintegrally formed, and the integral formation may be an inorganicinsulating material including an inorganic material. The inorganicmaterial may include a silicon nitride, a silicon oxide, and/or asilicon oxynitride.

One side of each of the plurality of branches 420 may be in contact withthe first main body 410 a, and the opposite side thereof may be incontact with the second main body 410 b. Accordingly, when viewed on aplane, the plurality of branches 420 may be disposed between the firstand second main bodies 410 a and 410 b and may be surrounded by thefirst and second main bodies 410 a and 410 b. Each of the plurality ofbranches 420 is spaced apart from an adjacent branch by a predeterminedinterval, and cavities 430 may be disposed between the plurality ofbranches 420.

The reinforcing member 400 may have a ladder shape when viewed on aplane.

When an impact is applied to the substrate 100, a crack caused by theimpact progresses along the first main body 410 a, the plurality ofbranches 420, and the second main body 410 b, so that a progress path ofthe crack may be increased. When the progress path of the crack isincreased, a part of the crack may be dispersed and blocked when thecrack progresses from the reinforcing member 400 to the display area DA(see FIG. 2). Accordingly, even when an impact is applied to thesubstrate 100, it is possible to minimize the progress of a crack causedby the impact from extending to the display area DA.

Next, referring to FIGS. 3 and 7B, the reinforcing member 400 includes afirst main body 410 a and a second main body 410 b, which are extendedin a predetermined direction (for example, a vertical direction) andface each other. Further, the reinforcing member 400 includes aplurality of first branches 420 a and a plurality of second branches 420b disposed between the first main body 410 a and the second main body410 b.

One side of each of the plurality of first branches 420 a may be incontact with the first main body 410 a, and the other side thereoffacing the one side may be in contact with the second main body 410 b.One side of each of the plurality of second branches 420 b may be incontact with the second main body 410 b, and the other side thereoffacing the one side may be in contact with the first main body 410 a.Here, the one side of each of the plurality of first branches 420 a maybe in contact with the other side of each of the plurality of secondbranches 420 b, and the other side of each of the plurality of firstbranches 420 a may be in contact with the one side of each of theplurality of second branches 420 b.

The plurality of first branches 420 a and the plurality of secondbranches 420 b may be disposed between the first and second main bodies410 a and 410 b while crossing one another. Cavities 430 may be disposedbetween the plurality of first branches 420 a and the plurality ofsecond branches 420 b.

When viewed on a plane, the plurality of first branches 420 a and theplurality of second branches 420 b may be surrounded by the first andsecond main bodies 410 a and 410 b, and may be disposed between thefirst and second main bodies 410 a and 410 b and may cross the areasbetween the first and second main bodies 410 a and 410 b from side toside.

FIGS. 8A to 8C are top plan views illustrating a disposition of theplurality of reinforcing members of FIG. 3.

First, referring to FIGS. 3 and 8A, first to third reinforcing memberunits 400 a, 400 b, and 400 c may be disposed in the non-display areaNDA of the substrate 100.

The first reinforcing member 400 a is disposed between the dam unit 300of the substrate 100 and the second reinforcing member 400 b, the secondreinforcing member 400 b is disposed between the first reinforcingmember 400 a and the third reinforcing member 400 c, and the thirdreinforcing member 400 c is disposed between the border of the substrate100 and the second reinforcing member 400 b. Herein, first to thirdreinforcing members 400 a, 400 b, and 400 c may each be an inorganicinsulating material including an inorganic material.

The first reinforcing member 400 a and the second reinforcing member 400b may each extend in a predetermined direction (for example, a verticaldirection), and may each have a rectangular shape including straightsides.

The third reinforcing member 400 c includes a main body 410 and aplurality of branches 420 protruding from the main body 410. The mainbody 410 may extend in the predetermined direction. The plurality ofbranches 420 may protrude in a different direction from the direction ofextension of the main body 410. For example, when the main body 410extends in the predetermined direction, the plurality of branches 420may extend in a diagonal direction inclined with respect to thepredetermined direction.

When viewed on a plane, each of the plurality of branches 420 mayprotrude from one surface of the main body 410 and may have arectangular shape including a side formed of a straight line. Each ofthe plurality of branches 420 is spaced apart from an adjacent branch bya predetermined interval, and cavities 430 may be disposed between thebranches.

The third reinforcing member 400 c, which is disposed at the outermostside among the first to third reinforcing members 400 a, 400 b, and 400c, may have a comb shape when viewed on a plane. The third reinforcingmember 400 c may disperse and block a crack caused by an impact when theimpact is applied to the substrate 100.

It is illustrated that the third reinforcing member 400 c disposed atthe outermost side among the first to third reinforcing members 400 a,400 b, and 400 c includes the main body 410 and the plurality ofbranches 420, but the present disclosure is not limited thereto. Forexample, as illustrated in FIG. 8B, each of the first to thirdreinforcing members 400 a, 400 b, and 400 c may include the main body410 and the plurality of branches 420 protruding from the main body 410.

Further, the first to third reinforcing members 400 a, 400 b, and 400 cmay be disposed within the non-display area while being spaced apartfrom one another by a predetermined interval, but the present inventionis not limited to that particular arrangement of the reinforcing members400 a, 400 b, and 400 c. For example, as illustrated in FIG. 8C, theplurality of branches 420 of each of the first to third reinforcingmembers 400 a, 400 b, and 400 c may be in contact with the main body ofthe adjacent reinforcing member. For example, one surface (for example,the surface from which the plurality of branches 420 does not protrude)of the main body 410 of the first reinforcing member 400 a may be incontact with the plurality of branches 420 of the second reinforcingmember 400 b, and one surface (for example, the surface from which theplurality of branches 420 does not protrude) of the main body 410 of thesecond reinforcing member 400 b may be in contact with the plurality ofbranches 420 of the third reinforcing member 400 c.

FIG. 9 is a circuit diagram corresponding to one pixel in the displaydevice illustrated in FIG. 1, FIG. 10 is a top plan view correspondingto one pixel of FIG. 9, and FIG. 11 is a cross-sectional view takenalong line II-II′ of FIG. 10. In FIG. 9, thin film transistors includedin a pixel are set with an NMOS, however, other forms of thin filmtransistors may be used, for example, the thin film transistors may beset with a PMOS.

Referring to FIGS. 1, and 9 to 11, the display device includes asubstrate 100, a wiring unit, and pixels PXL. Each pixel PXL displays animage, and the plurality of pixels PXL may be disposed and arranged in amatrix form, but FIGS. 9 and 10 illustrate only one pixel PXL forconvenience of the description. Herein, each pixel is illustrated in arectangular shape, but the shape of the pixel is not limited thereto,and the pixel PXL may be modified in various shapes.

The pixels PXL are disposed on the substrate 100.

The wiring unit provides a signal to the pixel PXL, and includes a scanline SL, a data line DL, and a driving voltage line ELVDD.

The scan line SL extends in a predetermined direction (for example, ahorizontal direction). The data line DL extends in another directioncrossing the scan line SL. The driving voltage line ELVDD may extend inthe substantially same direction as either the scan line SL or the dataline DL, for example, the driving voltage line ELVDD may extend in thedirection of extension of the data line DL. The scan line SL transmits ascan signal to a thin film transistor, the data line DL transmits a datasignal to the thin film transistor, and the driving voltage line ELVDDprovides a driving voltage to the thin film transistor.

The pixel PXL includes a thin film transistor connected to the wiringunit, an organic light emitting diode OLED connected to the thin filmtransistor, and a capacitor Cst.

The thin film transistor may include a driving thin film transistor TFT2for controlling the organic light emitting diode OLED and a switchingthin film transistor TFT1 for switching the driving thin film transistorTFT2. According to an exemplary embodiment of the present disclosure,one pixel PXL may include the two thin film transistors TFT1 and TFT2and one capacitor Cst, but the pixel PLX may be alternatively arranged.

The switching thin film transistor TFT1 includes a first gate electrode130 a, a first drain electrode 140 a, and a first source electrode 150a. The first gate electrode 130 a is connected to the scan line SL, andthe first drain electrode 140 a is connected to the data line DL. Thefirst source electrode 150 a is connected to a terminal of one side ofthe capacitor Cst. The switching thin film transistor TFT1 transmits adata signal applied to the data line DL to the capacitor Cst accordingto a scan signal applied to the scan line SL.

The capacitor Cst charges a voltage corresponding to the data signal.

The driving thin film transistor TFT2 includes a second gate electrode130 b, a second drain electrode 140 b, and a second source electrode 150b. The second gate electrode 130 b is connected to a terminal of oneside of the capacitor Cst, the second drain electrode 140 b is connectedto the driving voltage line ELVDD, and the second source electrode 150 bis connected to the organic light emitting diode OLED.

The switching thin film transistor TFT1 and the driving thin filmtransistor TFT2 may each include a first active pattern 120 a and asecond active pattern 120 b, each of which is formed of a semiconductormaterial. Each of the first active pattern 120 a and the second activepattern 120 b includes a source region SP, a drain region DP, and achannel region CP. The first active pattern 120 a and the second activepattern 120 b may each be a semiconductor pattern formed of polysilicon,amorphous silicon, an oxide semiconductor, and/or an organicsemiconductor material. Here, when the first active pattern 120 a andthe second active pattern 120 b are formed of the oxide semiconductor,the oxide semiconductor may include an amorphous oxide semiconductor ora crystalline oxide semiconductor.

A passivation layer 145 is formed on the switching thin film transistorTFT1 and the driving thin film transistor TFT2. The passivation layer145 may cover the switching thin film transistor TFT1 and the drivingthin film transistor TFT2 and may include one or more layers. Thepassivation layer 145 includes a contact hole exposing a part of thesecond source electrode 150 bb.

The organic light emitting diode OLED includes a light emitting layer170, a first electrode 160, and a second electrode 180. The lightemitting layer 170 is interposed between the first electrode 160 and thesecond electrode 180.

The first electrode 160 is connected to the second source electrode 150b of the driving thin film transistor TFT2. The first electrode 160serves as an anode electrode and is an electrode for injecting holes,and may include a material having a high work function.

A pixel defining layer 155, which divides a pixel area so as tocorrespond to each pixel PXL, is disposed on the substrate 100 on whichthe first electrode 160 and the like is disposed. The pixel defininglayer 155 may be an organic insulating layer formed of an organicmaterial. The pixel defining layer 155 may include an organic insulatingmaterial, such as a polyacrylic compound, a polyimide compound, afluorinate carbon compound, such as Teflon, and/or a benzocyclobutenecompound.

The light emitting layer 170 emits light according to an output signalof the driving thin film transistor TFT2 and displays an image byselectively emitting light. Herein, light emitted from the lightemitting layer 170 may be changed according to a material of the lightemitting layer 170, and may be a single-color light or white light.

The second electrode 180 may include a material having a lower workfunction than that of the first electrode 160. For example, the secondelectrode 180 may include molybdenum (Mo), tungsten (W), silver (Ag),magnesium (Ag), aluminum (Al), platinum (Pt), palladium (Pd), gold (Au),nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), lithium (Li),calcium (Ca), and/or an alloy thereof.

An encapsulation layer 200 protecting the organic light emitting diodeOLED from moisture or oxygen of the outside is disposed on the organiclight emitting diode OLED.

The capacitor Cst is connected between the second gate electrode 130 bof the driving thin film transistor TFT2 and the organic light emittingdiode OLED. The capacitor Cst includes a first capacitor electrode CE1connected to the first source electrode 150 a of the switching thin filmtransistor TFT1, and a second capacitor electrode CE2 disposed on thefirst capacitor electrode CE1. The capacitor Cst charges and maintains adata signal input into the second gate electrode 130 b of the drivingthin film transistor TFT2.

The display device according to an exemplary embodiment of the presentinvention may include a touch screen.

FIG. 12 is a cross-sectional view schematically illustrating anarrangement in which the display device of FIG. 11 includes a touchscreen.

Referring to FIGS. 11 and 12, a touch screen 250 may be disposed on theencapsulation layer 200.

The touch screen 250 may recognize a touch event to the display device.The touch event may be a hand of a user or a separate input means, suchas a stylus, making contact with, and/or held in close proximity to thesurface of the touch screen 250. The touch screen 250 includes sensingelectrodes to detect a touch and/or a degree of pressure applied by thetouch event. For example, the touch screen 250 may be implemented by acapacitance type or a piezo-resistive type touch screen. The capacitancetype touch screen includes a mutual capacitance type which senses achange in capacitance by a mutual operation between two sensingelectrodes, and a self-capacitance type touch screen which senses achange in capacitance of the sensing electrode itself.

The touch screen 250 may be formed by a method of directly forming thesensing electrodes on the encapsulation layer 200, a method oflaminating a thin film having a film form including the sensingelectrode on the encapsulation layer 200, or the like.

The touch screen 250 may include the sensing electrodes, and aninsulating layer disposed between the sensing electrodes.

The sensing electrodes may be directly formed on a flexible film. Theinsulating layer may include an inorganic insulating material and/or anorganic insulating material. When the insulating layer is an organicinsulating material, flexibility of the touch screen 250 may beincreased.

The display device, according to the exemplary embodiment of the presentdisclosure, may lack a polarizing layer for the sake of compactness. Inthe display device, in which the polarizing layer is omitted, a colorfilter and a black matrix may substitute for the function of thepolarizing layer. In this case, the color filter and the black matrixmay be disposed on the encapsulation layer 200. For example, the colorfilter and the black matrix may be directly disposed on theencapsulation layer 200 through a mask process using a mask.

The black matrix may be substituted with the pixel defining layer 155disposed under the encapsulation layer 200. In this case, the pixeldefining layer 155 may be a black pixel defining layer formed of athermosetting resin including black pigment. The pixel defining layer155 includes the black pigment, so that the dam unit 300 (see FIG. 3),which is formed of the same material in the same process step as thoseof the pixel defining layer 155, may include the black pigment.

At least a part of the display device, according to an exemplaryembodiment of the present disclosure, may be flexible, and the displaydevice may be arranged into various forms, such that at least a part ofthe display device is bent, folded, or rolled.

The display device, according to an exemplary embodiment of the presentdisclosure, may be applied to various electronic devices. For example,the display device may be applied to a television, a personal computersuch as a notebook computer, a mobile phone, a smart phone, a tabletcomputer, a Portable Multimedia Player (PDP), a Personal DigitalAssistant (PDA), a navigation guidance device, various wearable devices,such as a smart watch, and the like.

Although the present disclosure has been described with reference to theexemplary embodiments, those skilled in the art may understand that thepresent disclosure may be variously modified and changed withoutdeparting from the spirit and the scope of the present disclosure.

What is claimed is:
 1. A display device, comprising: a substrateincluding a display area, in which an image is displayed, and anon-display area, the non-display area being disposed on at least oneside of the display area; a plurality of pixels disposed in the displayarea; a passivation layer disposed on the substrate; a pixel defininglayer disposed on the passivation layer; an encapsulation layer disposedon the plurality of pixels; and a dam unit disposed in the non-displayarea, wherein the dam unit includes a body part and at least oneprotrusion which protrudes from the body part in a direction away fromthe display area, wherein the passivation layer and the pixel defininglayer each include an organic material, and wherein the dam unitincludes an organic material.
 2. The display device of claim 1, wherein:the body part extends in a first direction, the at least one protrusioncomprises a plurality of protrusions, and each of the plurality ofprotrusions protrudes in a second direction that crosses the firstdirection.
 3. The display device of claim 2, wherein the body part andthe plurality of protrusions are integrally formed.
 4. The displaydevice of claim 2, wherein each of the plurality of protrusions isspaced apart from an adjacent protrusion of the plurality of protrusionsby a predetermined interval.
 5. The display device of claim 4, whereincavities are disposed between each pair of proximate protrusions of theplurality of protrusions.
 6. The display device of claim 5, wherein awidth of each of the plurality of protrusions decreases farther awayfrom the body part.
 7. The display device of claim 6, wherein a width ofeach of the cavities increases farther away from the body part.
 8. Thedisplay device of claim 2, wherein the plurality of protrusions isirregularly disposed along a region of the substrate.
 9. The displaydevice of claim 1, wherein the dam unit is disposed in plural within anarea that surrounds the border between the non-display area and thedisplay area.
 10. The display device of claim 1, further comprising areinforcing member disposed in the non-display area and including a mainbody and at least one branch which extends in a direction toward thedisplay area, wherein the at least one branch of the reinforcing memberextends in a diagonal direction inclined with respect to a direction ofextension of the main body of the reinforcing member.
 11. The displaydevice of claim 1, wherein the dam unit is disposed on a same layer asthat of the pixel defining layer.
 12. The display device of claim 1,wherein the dam unit is disposed on a same layer as that of thepassivation layer.
 13. The display device of claim 1, wherein the damunit includes a first organic insulation pattern and a second organicinsulation pattern, which are sequentially laminated on the substrate inthe non-display area.
 14. The display device of claim 13, wherein thefirst organic insulation pattern is disposed on a same layer as that ofthe passivation layer, and the second organic insulation pattern isdisposed on a same layer as that of the pixel defining layer.
 15. Adisplay device, comprising: a substrate including a display area and anon-display area abutting the display area; a plurality of pixelsdisposed within the display area, each of the plurality of pixelsincluding a light emitting element; an encapsulation layer, including anorganic material, disposed on the plurality of pixels; a baffle disposedin the non-display area of the substrate; and a reinforcing memberdisposed in the non-display area, wherein the baffle is covered by theencapsulation layer, the baffle includes at least one protrusion, andthe at least one protrusion extends in a direction away from the displayarea, wherein the reinforcing member includes a main body and at leastone branch which extends in a direction toward the display area, andwherein the at least one branch of the reinforcing member extends in adiagonal direction inclined with respect to a direction of extension ofthe main body of the reinforcing member.
 16. The display device of claim15, wherein: the at least one protrusion comprises a plurality ofprotrusions, and the baffle is disposed in plural and there is a cavityformed between each pair of proximate protrusions of the plurality ofprotrusions.
 17. The display device of claim 16, further comprising alight unit configured to cast a light upon the plurality of protrusionsand to thereby produce an interference pattern that indicates a boundaryof the organic material of the encapsulation layer.
 18. The displaydevice of claim 16, wherein each pair of proximate protrusions of theplurality of protrusions is separated by a single spacing.
 19. Thedisplay device of claim 16, wherein each pair of proximate protrusionsof the plurality of protrusions is separated by a spacing that decreasesor increases as a distance between the corresponding pair of proximateprotrusions relative to the display area increases.
 20. The displaydevice of claim 15, further comprising: a passivation layer disposed onthe substrate; and a pixel defining layer disposed on the passivationlayer, wherein the passivation layer and the pixel defining layer eachinclude an organic material.